IB Design Technology Topic A3.1: Material Classification and Properties Key Definitions

A biomaterial is any material that is produced by or originates from biological organisms, such as plants, animals, bacteria, or fungi.

Chemical properties are characteristics that describe how a material reacts with other substances, resulting in a change in its chemical composition.

A chemical property is a characteristic of a material that only becomes noticeable during or after a chemical reaction.

The circular economy is an economic model where resources are kept in use for as long as possible, allowing for the maximum value to be extracted while they are in use. At the end of a product’s life, materials are recovered and regenerated, reducing waste and supporting sustainable design and production.

A material comprised of two or more materials to improve their physical,
mechanical and chemical properties and/or aesthetics characteristics.

The ability of a material to withstand forces that try to squash or compress it without breaking or deforming.

The ability of a material to resist damage caused by oxidation (like rust) or other chemical reactions with substances such as water, acids, or salts.

The mass per unit volume of a material (usually measured in kg/m³ or g/cm³). Its a measure of mass divided by volume (ρ = m/V)

The ability of a material to be stretched, drawn, or extruded into a long, thin shape such as a wire, without breaking.

The ability of a material to return to its original shape after being stretched, compressed, or deformed, once the force is removed.

Electrical conductivity is a measure of how easily electricity flows through a material. It is the inverse of resistivity

Measures how much a material resists the flow of electricity.

Electro-rheostatic (ER) fluids are special liquids that can quickly become thicker or more solid when an electric field is applied. When the electricity is turned off, they go back to being a normal liquid. This makes them useful in things like shock absorbers and brakes.

A measure of how easily and quickly a material can be ignited and how fast it burns once on fire.

A hard, brittle and typically transparent amorphous solid made by rapidly
cooling a fusion of sand, soda and lime.

The ability of a material to resist scratching, indentation, or penetration.

A chemical property that describes a material’s ability to absorb moisture from the surrounding air.

Magneto-rheostatic (MR) fluids are special liquids that become thicker or more solid when a magnetic field is applied. When the magnetic field is removed, they return to their normal liquid state. This makes them useful in things like car suspension systems and vibration control.

The ability of a material to be permanently deformed (flattened or shaped) by compressive forces without cracking or breaking.

Mechanical properties are characteristics that describe how a material behaves when forces are applied, such as tension, compression, bending, or impact.

Mechanical properties are the characteristics of a material that describe how it reacts to forces such as stretching, compressing, or bending, and how it behaves under stress and strain.

The temperature at which a material changes from a solid to a liquid.

Photochromic materials change color in response to light and revert when the light is removed.

Physical properties are characteristics that can be observed or measured without altering the material's chemical composition.